This training grant proposal on the The cellular and molecular foundations of biomedical sciences is a renewal of a successful program started eleven years ago. It seeks to train graduate students in the broad fundamentals of biomedical sciences to provide them with the tools to understand important problems in modern biology and health. This is accomplished initially through Core course modules in the first year covering Genetics, Molecular Biology, Structural Biology, Biophysics, Cell Biology and Genomics and Systems Biology. Students follow this with electives in specific fields of their interest. The program is based in the Department of Biological Sciences, but has been expanded to include established faculty from Columbia's College of Physicians and Surgeons as well as faculty in the Department of Chemistry. Students undertake rotations in up to three laboratories and can do their thesis work with any of the 55 faculty in the program, roughly half of which are on the Medical School and Main campuses, respectively. This has provided expanded opportunities for training of the students in outstanding laboratories and has fostered collaboration between faculty and students at Columbia's Medical School and main campuses. The faculty work in a broad range of fields including structural biology, molecular biology, microbiology, genetics, bioinformatics and systems biology, developmental biology and neurobiology. Experimental systems are also broad including bacteria, yeast, drosophila, C. elegans, frogs and mice. Human tissue culture systems are also utilized and most systems consider problems relevant to human health and physiology. Ten graduate student traineeships are requested per year to support five students for two years each, usually in their third and fourth years. This will fund 14.5% of our current training grant eligible student pool of 69. The best students in our program will be chosen to be funded by this grant. This will be determined by their performance in the Core and other courses, recommendations from their rotation and thesis sponsors, and a short research proposal reviewed by the grant's steering committee. The qualifications of the faculty and the research facilities at Columbia are outstanding and provide a superb training environment for the students. The record of outstanding publications by the students also demonstrates the success of this program.